Rotary bench stripper



Nov. 15, 1966 D. OEHLERKING ROTARY BENCH STRIPPER Original Filed Feb. 10 1964 2 Sheets-Sheet 1 INVENTOR.

Nov. 15, 1966 Original Filed Feb. 10

2 Sheets-Sheet 2 a 2 J W M AW n; E d W/ f M a 47 Z 4 M %fl 5 4 6/ %w W, 1W 8 C .1 Z 0 I 66 2 3 JTJM 7 ,0 l rlll 1G1 @Iiw--- A 7 mm /4 United States Patent This is a continuation of Serial No. 344,170, now abandoned, filed February 10, 1964 This invention relates to a rotary wire stripper of the type having a blade which rotates about a wire to be' stripped.

A primary object of the invention is a wire stripper of this type including an improved blade mounting for providing a positive stripping action.

Another object is a wire stripper of this type having means for precise and fine adjustment of the position of the stripping blade.

Another object is a rotary wire stripper including a single blade constructed for spiral deflection, and a wire guide positioned opposite the'blade for holding the wire.

Another object is a rotary wire stripper of this type, including an improved spring mounting for the blade which provides a first angle between the blade and wire for cutting, and a second angle for removing the insula tion slug.

Another object is a wire stripper of this type which may be bench mounted.

Another object is a Wire stripper of this type having a reversible stripping blade.

Another object is a rotary wire stripper of this type using a rotatable round blade.

Another object is a reliably operable rotary wire stripper which is compact and inexpensive to manufacture.

In the drawings:

FIGURE 1 is a side elevation of my wire stripper;

FIGURE 2 is an enlarged side view of the stripper head of FIGURE 1;

FIGURE 3 is an end view of the stripper head of FIGURE 2;

FIGURE 4 is an end view of the stripper head of FIGURE 2 with the blade holder removed and with portions broken away for clarity;

FIGURE 5 is an enlarged end view of the back of the stripper head showing the blade mounting;

FIGURE 6 is a section along plane 6-6 of FIG- URE 5;

FIGURE 7 is a back view, similar to FIGURE 5, but with the cover in position;

FIGURE 8 is a partial section through the stripper head illustrating movement of the blade when a wire is positioned for stripping;

FIGURE 9 is a section, similar to FIGURE 8, showing the position of the blade after it has cut through the wire to be stripped;

FIGURE 10 is a front view of a modified form of blade; and

FIGURE 11 is a section through a further form.

In FIGURE 1, the stripper head is indicated generally at 10 and a drive motor for the head is indicated at 12. A shaft 14 may connect the motor 12 and the stripper head 10. The combination of the motor and head may be suitably mounted on a bench or the like.

The stripper head 10 may include a spinner or frame at 16 in FIGURE 2, which is generally cylindrical in form having a rear section 18 which is attached to the drive shaft 14 by means of a set screw'20 or the like, and a front section at 22. The front section 22 may 'ice include a blade holder 24. The front section 22 may also include a rim or shoulder 26 which holds the blade holder 24, there being a plurality of set screws 28 or the like for mounting the blade holder to the spinner.

The blade holder 24 has an outer generally cylindrical section 30 which mounts a Wire guide 32 at its center. The wire guide may have a somewhat conical opening 34 for receiving a wire to be stripped and a passage 36 in which the wire to be stripped is positioned. A portion of the wire guide is cut away, as at 38, so that the wire to be stripped will be exposed to the cutting blade. The blade holder 24 has an inner generally cylindrical section 40 with a slot or groove 42 illustrated in FIGURE 5. In the slot 42 is mounted a column support block 44 having an extension or section 46 for adjusting the position of the blade relative to the wire guide. The support block 44 will slide in grooves 43 on either side of slot 42. Rigidly attached to the column support block 44 by a screw 47 is a spring 48, which is preferably a laminated leaf spring, but which may be otherwise, and mounts a blade 60 at its inner end. The blade 60 may have a cutting edge 62 adjacent the wire guide and a second cutting edge 64 positioned away from the wire guide. Each cutting edge is defined between a flat forward face 65 and a relieved face 65a which intersect at an angle A. The cutting edge 64 may be used when the cutting edge 62 is dulled to make the blade reversible. Attached to the forward face of the spring 48 and to the blade 60 is a block 66 which has a surface 68 which slants radially inwardly and away from the wire insertion opening 34. The column support block 44 has a mating slanted surface 70.

The section 46 of support block 44 may mount a threaded screw 72, the opposite end of which is threadedly engaged with a portion of the cylindrical section 40 of the blade holder. A coil spring 74 or the like may encircle the screw 72 between the column support block 44 and the cylindrical section 42 to prevent any backlash between the blade and blade holder and to provide a positive adjustment action between the two. It is preferred that the pitch of the threads between screw 72 and the column support block 46 be different than the pitch of the threads between the screw and the cylindrical section 40 of the blade holder. -In this way there is provided a differential movement when the screw 72 is turned and thus a fine adjustment of the position of the cutting blade. For example, one thread might be 40 turns per inch and the other thread 32 turns per inch. Thus movement of screw 72 through a single turn would provide blade movement of approximately .006 inch. It makes no difference which end of the screw has the greater pitch.

An opening 76 may be formed in the rim 26 so that an adjusting tool will have access to the screw 72. The spinner is completed by an adjustable wire stop 78 positioned in the open section between the back 18 and the front '22 and there may be a scale or the like 80 positioned along one side of the spinner. A cover plate 82 in FIGURE 7 may close section 40 except for the adjustable column support block and stripping blade.

FIGURE 10 shows a modified form of blade. Blade may be round and fixed to spring 92 by a screw 94 or the like. The blade is adjustable and may be rotated whenever a certain section of the cutting edge becomes dull. In effect, blade 90 provides a large number of cutting edges on a single blade.

FIGURE 11 shows a similar blade except that it may rotate relative to its mounting spring. Round blade 96 is mounted on spring 98 by a rivet 100 or the like. The frictional force between the blade and stationary wire causes the blade to rotate relative to the wire as the head-rotates.

The use, operation and function of the invention are as follows:

The wire to be stripped is pushed through the open ing 34 and lays in the trough 36 of the wire guide. The bladel and the entire stripping head is rotated. As the wire is withdrawn the blade will dig in to cut the insulation. Because the blade is rotating, it will cut completely around the wire. The wire is removed but the blade may hold the slug of insulation within the stripping head. The next stripping operation will remove the slug of insulation.

The device has the advantage that the cutting edge of the blade will be at a relatively sharp angle for cutting the insulation and a relatively fiat angle for stripping. For example, as the wire is withdrawn, the fiat spring 48 will flex or deform allowing the edge 62 to stay at a relatively sharp angle. As the cutting edge cuts through the insulation caused by the Wire being withdrawn further, the flat spring will straighten out and the flat surface 65a of the blade itself will assume a collet position. Thus, the slug of separated insulation will be actually forced off of the wire by a collet action.

As the wire is withdrawn, the cutting edge 62 might tend to pass overcenter, meaning to the right of the plane of the flat spring itself. But the mating surfaces 68- and 70 on the block and blade holder will prevent the cutting edge from moving much, if any, past dead center. Thus, the mating surfaces 68 and 70, regardless of their angle, will prevent the flat spring from bowing in the opposite direction. The surfaces, in effect, add rigidity to the flat spring, but only in one direction.

It is advantageous to have a relatively large angle between the cutting surface of the blade and the wire to be stripped for initially severing or cutting the insulation on the wire. However, once the insulation has been cut, as illustrated in FIGURE 9, it is advantageous to have a substantially smaller angle between the cutting face of the blade and the wire. The advantage of a low blade angle for removing the insulation is that the colleting action of the blade keeps the wire from bouncing into the blade and being nicked or scratched. By having a somewhat sharp angle to initially cut the insulation it is possible to have the blade adjusted slightly further from the center of the wire than if there was a somewhat smaller cutting angle. This, of course, has the advantage of removing the blade farther from the wire to prevent any chance of nicking. The particular bending or flexing action of spring 58 provides a high or sharp blade angle for cutting and a relatively lower angle for stripping.

The difierentia-l screw for moving the blade relative to the wire guide is important as it provides a very fine adjustment. To provide this same precision with a constant pitch screw would require a thread much too fine for practical production methods.

The entire unit or stripping head may be driven by a motor or any other means satisfactory :for rotating the head. In many applications the stripper and motor will be bench mounted, although this is not necessary.

The advantage of having a laminated spring for mounting the blade is that there is less stress per spring leaf. This is important in providing a spring with long lift.

The stripping head shown is effective to remove any common type of insulation. The wire may be either braided or single strand. The invention is particularly useful, because of its precision adjustment, in stripping small wire sizes such as used in the aircraft and missile industries.

The round blades of FIGURES 10 and 11 provide a number of cutting areas on a single blade. In the case of the fixed blade of FIGURE 10, it may be adjusted to a 4 new cutting area. The blade of FIGURE 11 rotates providing slight, but even, wear around the blade.

Whereas the preferred form of the invention has been shown and described herein, it should be realized that there are many modifications, substitutions and alterations thereto within the scope of the invention.

I claim:

1. In a rotary wire stripper, a blade holder and means for rotating it, a blade structure including a wire stripping cutting edge, a generally fiat spring mounting the blade structure to said blade holder for back and forth movement, means on the blade holder and cooperating means on the blade structure for causing the wire stripping cutting edge to be deflected to one angle for cutting and to a second angle for stripping when moved by a wire to be stripped, a wire guide attached to the blade holder and positioned to support a wire to be stripped, and an opening in the blade holder in alignment with the cutting edge and wire guide for receiving a wire to be stripped.

2. The structure of claim 1 further characterized by and including a support block on the blade holder and mounting the flat spring, the support block and wire guide having cooperating surfaces which prevent the cutting edge from flexing beyond the plane of the support of the blade holder at the end of a stripping operation when the wire is being withdrawn.

3. The structure of claim 2 further characterized in that the surface between the support block and the blade structure is at an acute angle relative to the plane of the flat spring.

4. In a rotary wire stripper, a blade holder and means for rotating it, a blade structure including a wire stripping cutting edge, means mounting the blade structure on the blade holder for back and forth movement, a wire guide attached to the blade holder and positioned to support a wire to be stripped, an opening in the blade holder in alignment with the cutting edge and wire guide for receiving a wire to be stripped, and a differential screw for adjusting the radial position of the blade structure on the blade holder relative to the opening, including a member threaded to the blade structure and also threaded to the blade holder, the threads between the member and blade holder being at a different pitch than the threads between the member and blade structure.

5. In a rotary wire stripper, a blade holder and means for rotating it, a blade structure including a wire stripping cutting edge, a generally flat spring mounting the blade structure to the blade holder for back and forth movement, means on the blade holder and cooperating means on the blade structure for causing the wire stripping cutting edge to be deflected to a relatively large angle for cutting the insulation and to a relatively smaller angle for stripping the insulation, a wire guide attached to the blade holder and positioned to support a wire to be stripped, and an opening in the blade holder in alignment with the cutting edge and wire guide for receiving a wire to be stripped.

6. The structure of claim 5 further characterized by and including means for adjusting the blade structure relative to the wire guide including a member threaded to the blade structure and blade holder, the threads between the member and blade holder being at a different pitch than the threads between the member and blade structure.

References Cited by the Examiner UNITED STATES PATENTS 9/1902 Reid 2791l2 1/ 1963 Carpenter 819.51 

1. IN A ROTARY WIRE STRIPPER, A BLADE HOLDER AND MEANS FOR ROTATING IT, A BLADE STRUCTURE INCLUDING A WIRE STRIPPING CUTTING EDGE, A GENERALLY FLAT SPRING MOUNTING THE BLADE STRUCTURE TO SAID BLADE HOLDER FOR BACK AND FORTH MOVEMENT, MEANS ON THE BLADE HOLDER AND COOPERATING MEANS ON THE BLADE STRUCTURE FOR CAUSING THE WIRE STRIPPING CUTTING EDGE TO BE DEFLECTED TO ONE ANGLE FOR CUTTING AND TO A SECOND ANGLE FOR STRIPPING WHEN MOVED BY A WIRE TO BE STRIPPED, A WIRE GUIDE ATTACHED TO THE BLADE HOLDER AND POSITIONED TO SUPPORT A WIRE TO BE STRIPPED, AND AN OPENING IN THE BLADE HOLDER IN ALIGNMENT WITH THE CUTTING EDGE AND WIRE GUIDE FOR RECEIVING A WIRE TO BE STRIPPED. 